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set default_storage_engine=innodb;
create or replace table dept (
dept_id int(10) primary key,
name varchar(100)
)
with system versioning;
create or replace table emp (
emp_id int(10) primary key,
dept_id int(10),
name varchar(100),
salary int(10),
constraint `dept-emp-fk`
foreign key (dept_id) references dept (dept_id)
on delete restrict
on update restrict
)
with system versioning;
select now() into @ts_0;
insert into dept (dept_id, name) values (10, "accounting");
commit;
select row_start into @ts_1 from dept where dept_id=10;
insert into emp (emp_id, name, salary, dept_id) values (1, "bill", 1000, 10);
commit;
select row_start into @ts_2 from emp where name="bill";
select * from emp;
emp_id dept_id name salary
1 10 bill 1000
update emp set salary=2000 where name="bill";
commit;
select row_start into @ts_3 from emp where name="bill";
select * from emp;
emp_id dept_id name salary
1 10 bill 2000
select * from emp for system_time as of timestamp @ts_2;
emp_id dept_id name salary
1 10 bill 1000
select * from emp for system_time as of timestamp @ts_3;
emp_id dept_id name salary
1 10 bill 2000
select * from emp e, dept d
where d.dept_id = 10
and d.dept_id = e.dept_id;
emp_id dept_id name salary dept_id name
1 10 bill 2000 10 accounting
select * from
emp for system_time from timestamp @ts_1 to timestamp @ts_2 e,
dept for system_time from timestamp @ts_1 to timestamp @ts_2 d
where d.dept_id = 10
and d.dept_id = e.dept_id;
emp_id dept_id name salary dept_id name
set statement system_versioning_asof=@ts_0 for
select * from emp e, dept d
where d.dept_id = 10
and d.dept_id = e.dept_id;
emp_id dept_id name salary dept_id name
set statement system_versioning_asof=@ts_1 for
select * from emp e, dept d
where d.dept_id = 10
and d.dept_id = e.dept_id;
emp_id dept_id name salary dept_id name
set statement system_versioning_asof=@ts_2 for
select * from emp e, dept d
where d.dept_id = 10
and d.dept_id = e.dept_id;
emp_id dept_id name salary dept_id name
1 10 bill 1000 10 accounting
set statement system_versioning_asof=@ts_3 for
select * from emp e, dept d
where d.dept_id = 10
and d.dept_id = e.dept_id;
emp_id dept_id name salary dept_id name
1 10 bill 2000 10 accounting
drop table emp, dept;
create table t1 (
a timestamp(6),
b timestamp(6) generated always as (a + interval 1 day),
c timestamp(6) generated always as (a + interval 1 month) stored,
d timestamp(6) generated always as row start,
e timestamp(6) generated always as row end,
period for system_time(d,e)
) with system versioning;
show columns from t1;
Field Type Null Key Default Extra
a timestamp(6) YES NULL
b timestamp(6) YES NULL VIRTUAL GENERATED
c timestamp(6) YES NULL STORED GENERATED
d timestamp(6) NO NULL STORED GENERATED
e timestamp(6) NO NULL STORED GENERATED
select table_catalog,table_schema,table_name,column_name,ordinal_position,column_default,is_nullable,data_type,character_maximum_length,character_octet_length,numeric_precision,numeric_scale,datetime_precision,character_set_name,collation_name,column_type,column_key,extra,column_comment,is_generated,generation_expression,'---' from information_schema.columns where table_name='t1';
table_catalog def
table_schema test
table_name t1
column_name a
ordinal_position 1
column_default NULL
is_nullable YES
data_type timestamp
character_maximum_length NULL
character_octet_length NULL
numeric_precision NULL
numeric_scale NULL
datetime_precision 6
character_set_name NULL
collation_name NULL
column_type timestamp(6)
column_key
extra
column_comment
is_generated NEVER
generation_expression NULL
--- ---
table_catalog def
table_schema test
table_name t1
column_name b
ordinal_position 2
column_default NULL
is_nullable YES
data_type timestamp
character_maximum_length NULL
character_octet_length NULL
numeric_precision NULL
numeric_scale NULL
datetime_precision 6
character_set_name NULL
collation_name NULL
column_type timestamp(6)
column_key
extra VIRTUAL GENERATED
column_comment
is_generated ALWAYS
generation_expression `a` + interval 1 day
--- ---
table_catalog def
table_schema test
table_name t1
column_name c
ordinal_position 3
column_default NULL
is_nullable YES
data_type timestamp
character_maximum_length NULL
character_octet_length NULL
numeric_precision NULL
numeric_scale NULL
datetime_precision 6
character_set_name NULL
collation_name NULL
column_type timestamp(6)
column_key
extra STORED GENERATED
column_comment
is_generated ALWAYS
generation_expression `a` + interval 1 month
--- ---
table_catalog def
table_schema test
table_name t1
column_name d
ordinal_position 4
column_default NULL
is_nullable NO
data_type timestamp
character_maximum_length NULL
character_octet_length NULL
numeric_precision NULL
numeric_scale NULL
datetime_precision 6
character_set_name NULL
collation_name NULL
column_type timestamp(6)
column_key
extra STORED GENERATED
column_comment
is_generated ALWAYS
generation_expression ROW START
--- ---
table_catalog def
table_schema test
table_name t1
column_name e
ordinal_position 5
column_default NULL
is_nullable NO
data_type timestamp
character_maximum_length NULL
character_octet_length NULL
numeric_precision NULL
numeric_scale NULL
datetime_precision 6
character_set_name NULL
collation_name NULL
column_type timestamp(6)
column_key
extra STORED GENERATED
column_comment
is_generated ALWAYS
generation_expression ROW END
--- ---
drop table t1;
|